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Diabetes Health Center

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Diabetes Basics

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What is diabetes? What are the types of diabetes?

Diabetes is a number of diseases that involve problems with the hormone insulin. Normally, the pancreas (an organ behind the stomach) releases insulin to help your body store and use the sugar and fat from the food you eat. Diabetes occurs when one of the following occurs:

  • When the pancreas does not produce any insulin
  • When the pancreas produces very little insulin
  • When the body does not respond appropriately to insulin, a condition called "insulin resistance"

Diabetes is a lifelong disease. Approximately 18.2 million Americans have the disease and almost one third (or approximately 5.2 million) are unaware that they have it. An additional 41 million people have pre-diabetes. As yet, there is no cure. People with diabetes need to manage their disease to stay healthy.

Recommended Related to Diabetes

Diabetes Care: Managing Your Time When You Have Diabetes

Sometimes, living with diabetes can seem like a full-time job -- trying to keep up with everything you need to do for proper diabetes care. "Diabetes is a very time-consuming disease to manage well," says Karmeen Kulkarni, MS, RD, CDE, and former president of health care and education for the American Diabetes Association. "The medication, the food, the physical activity -- you add life in general to that whole picture and it ends up being quite challenging."

Read the Diabetes Care: Managing Your Time When You Have Diabetes article > >

The Role of Insulin in Diabetes

To understand why insulin is important in diabetes, it helps to know more about how the body uses food for energy. Your body is made up of millions of cells. To make energy, these cells need food in a very simple form. When you eat or drink, much of your food is broken down into a simple sugar called "glucose." Then, glucose is transported through the bloodstream to the cells of your body where it can be used to provide some of the energy your body needs for daily activities.

The amount of glucose in your bloodstream is tightly regulated by the hormone insulin. Insulin is always being released in small amounts by the pancreas. When the amount of glucose in your blood rises to a certain level, the pancreas will release more insulin to push more glucose into the cells. This causes the glucose levels in your blood (blood glucose levels) to drop.

To keep your blood glucose levels from getting too low (hypoglycemia or low blood sugar), your body signals you to eat and releases some glucose from storage kept in the liver.

People with diabetes either don't make insulin or their body's cells are resistant to insulin, leading to high levels of sugar circulating in the blood, called simply high blood sugar. By definition, diabetes is having a blood glucose level of 126 milligrams per deciliter (mg/dL) or more after an overnight fast (not eating anything).

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